Multivoltage-speed controller.



No. 836,019. 4 PATENTED NOV. 13, 1906.

Y A. D. DU BOIS.

MULTIVOLTAGE SPEED CONTROLLER.

APPLIGATION FILED JAN.13.1906.

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winaiiefil V fizz/aniondlazaizdrjja fioekfi No. 836,019. PATENTED NOV. 13, 1906.

I A. D. DU 301s. MULTI'VOLTAGE SPEED CONTROLLER.

APPLICATION FILED JAN.13.1906.

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UNITED STATES PATENT oFFIoE- ALEXANDER D. ,DU 1301s, or crnoaoo. ILLINOIS, AssmNoaro WESTERN,

ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A- CORPORATION OF ILLIN 01S.

' MULTlVOLTAGE-SPEED CONTROLLEFI.

Specification of Letters Patent.

Patented Nov. 13, 1906.

Application iiledjJ'anuary 13. 1906. Serial No. 295,839?

of Illinois, have invented a certain new an useful Improvement in Multivoltage Speed Controllers, of which the following is a full, clear, concise, and exact description.

My invention relates to speed-control syss r'o terns for electric motors wherein both; varia' tions in the field strength and in the armatare-current are utilize to vary the speed of the motor.

The invention. has for its object to provide 1 5 an arrangement of circuits and apparatus whereby a motor may be employed in connection with circuits of varying voltage and g ven a wide range of speed.

My invention also contemplates a construction permitting the field-resistance controller, w ich is at all times independent of the armature-resistance controller, to be set for any desired speed with the armature on any desired voltage and the motor stopped 2 5 and started by operating the armature-resistance-controller without disturbing the adjustment of the field-controller.

' In accordance with my invention I.provide a switch-arm controlling thcconnection 3c of high and low voltage circuits with the mo tor-armature, the switch-arm being adapted [to be operated by mechanism controlled by Jthe field-resistance-controlling arm in its movement, said mechanism when operated 5 shifting the switch-arm from onc circuit to another. The field-resistance arm is adapted when it reaches a given point'in its travel as, for example, as it-passes from the last contact of the resistance to the first-to operate 40 said mechanism and shift the switch-arm,

for example, from the low-voltage to the high-voltage circuit. The field-resistance controller may then be moved to bring the entire resistance into the field-circuit, so that the motor is brought to full speed with a weakened field and the maximum of current in its armature.

A further feature of my mvention consists in placing the field resistance under the con- '50 trol of the armature-starting arm, the field r'esistance controller being, however, at all times independent of the starting-arm. With this arrangement the field-resistance con-.

troller may be set for any desired speed with the ''motor-armature in the high or low voltage circuit, as desired, and the motor started brought up to the desired speed, or stopped by simply operating the starting-arm without disturbing the adjustment of the fieldresistance controller. The startin -arm controls the interpolation of the pre etermined field resistance into the field-circuit, preferably by means ofshunts about succeeding sections of the field resistance, which are opened by the starting-arm in its movement to gradually cut the predetermined field resistance into the field-circuit. 1

I will describe my invention .by reference to the accompan ing drawings, in which Figure, 1 is a iagram illustrating the prefcrred embodiment thereof; and Figs. 2, 3,

and'4 are detail. views of the switch controllin 'the connection of the armature with the hig and low voltage circuits, showing the switch in its alternative positions.

The same characters of reference designate the same parts throughout the several figures of the drawings. y

I have shown my invention applied to a system of two voltages or the well-known three-wire system.

The armature a of the motor is included in the main conductor 1 between the line and the controlling arm b" of the armature-starting resistance'b. The arm I) is arranged to sweep over contacts of the usual resistance until it reaches the plate b whenthe resistance is all cut out of the armature-circuit. The plate 6 is connected by a conductor 4 with the contact 0 ofa knife-switch c. The mate contact a of said switch is connected with conductor 2, the neutral wire of the system, and the switch-arm c normally connects said contacts 0 0 together, so that when the starting-arm engages its contacts the armature is in the low-voltage circuit 124. Theswitch-arm 0 when moved out of engagement with its contacts 0 c is adapted to engage contacts 0 c and as it continues its movement is brought into en agernent with contact 0", connecting the tliree contacts together. Contact 0 is connected by cond uctor'5 with contact 0 on the other side of the switch-arm and by conductor 6, including a resistance R with contact 0 The contact 0 is connected with the main eonductor 3 leading to the line. When the switch-arm c is thrown into engagement cept its normal or dead position.

as seams with thecontactsc c, the armature is the ments 6 b. The field-resistance arm d is i high-voltage circuit 1 i563 but the resist ance B. being includeotin the circuit there will be no sudden increase of current in the armature A moment later when the armature attains normal speed the switch-arm engages the contact short-circuiting the resistance. 7

The field. F of the motor is included-in a conductor 7, extending from conductor 1 between the line and motor to the contact d of the field'resistance d. The controllinglevergd of the field resistance is connected by a conductor 8 with a segment 6 adapted to he engaged by an insulated plate 12 upon the under side of the armatureetartin arm I) in all positions of the starting-arm l2 em The insulated plate I) is arranged to connect the segment with a segment 6 connected by conductor 9 with main-line conductor 3, so that when thestarting-arm is advanced and bridges said segments While the controllinglever d of the field'resistance is on segment at the field F is at full strength in circuit l-78 '93. During the travehof the arm I) over its resistance-contacts the plate 12- engages a segment I), which is connectedb)? conductor 10 with conductor 7, including the field. A shunt is'thus established about the portion of the field circuit previously traced, including the field-resistancewontrolling arm and its contacts, so that no field resistance could be cut in until the armature resistance shall have beencut out.

As the starting-arm reaches segment I) the plate bf leaves segment I) and eiigages successively contacts b b, which control shunts 11 12 about successive portions did of the field resistance, so that no matter where the field resistance oontrolleris set upon the operation of the starting-arm the shunts will be successively opened and the predetermined field resistance gradually brought into the field pirouit. I

The field-resistance-controlling arm (2 controls the operation of the switch-arm 0 The shaft 01 of the field resistance to which is att'achcd the lever 03 carries a segmental gear said. field resistance, for connecting said'mo- 6, adapted to mesh with a segmental gear f, secured to the switch-arm. The gear f is provided with two concave portionsff In the normal positions of the apparatus, with the controlling-arm d on contact d and the switch-arm a connecting cont-acts c 0 the gears occupy the position shown in Fig. 1, with the teeth on gear e on the right side thereof and resting against the concave portionf of gear 7 at the right thereof and the teeth of gear f being on the left side thereof. Now assuming the motor is to he brought to its highest speed the starting-arm is thrown clear over until the armature resistance is all cut out and the plate I)?- engages the dead contact I), still connecting, however, se

then moved over its contacts, the gear e riding in the concave portion f of gear fwithout operating it. When the arm d reaches the last contact all the field resistance is 'cut into-the fiel -circuit, the armature still running on low-voltage current. The gear e occupies the position shown in Fig. 2. As the arm (1 leaves the last contact and engages contact d the teeth on gears e f mesh and the arm is swung into engagement with contacts c 0 whereupon the armature is con-.

nected with the high-voltagecircuit, but

with the resistance R in circuit, so that no I sudden rush of current passes throu h the armature. The contact (1 is madeo some length, and when the arm d is about to leave it the arm 0 is moved still farther to tlieleft, engaging contact 0 and shunting the resistance R, thus connecting the armature directly with the high-voltage mains. The gears now occupy the position shown in Fig;

.3 with'the smooth peripheralsurface of gear 6 resting in the concave portion f of gearf; The arm'd may now be moved until it reaches the last contact, whereupon the maximum motor speed is attained with weakened field and armature on hi h-voltage mains. The gears are nowin t e ositicn shown in Fig. 4, locked against furtiier clockwise movement. To return the parts to normal position, it is simply-necessary to move the lever d in a contra-clockwise direction twice around its contacts and reverse the starting-arm.

I claim- 1. In a multiple-voltage system of speed control for electric motors, the combination with a motor and its circuit, of an armature resistance for the motor, a controller for said resistance, a field resistance having a com troller independent of the starting-resistance controller, the interpolation of the amount of field resistancedetermined by the field-re sistance controller being governed b the starting-resistance controller, a plurality of sources of current of varying voltage, and means operated during the manipulation of tor armature with each of said sources of cur rent.

2. In a multiple-voltage system of speed .control for electric motors, the combination with a motor'and 1ts circuit, of an armaturecontrolled by said starting-resistance arm,

sources of current of high and low voltage, and mechanism operated by said field-resistance-controlling arm in its movement for seams i, to shift saici switchf contacts to the other, to

mt rewoitege s; stern of speed for eiectric the combination with a mo tor (3 13s 9 it, of armaturestarting 'itroiiingsrm,

2o inter-o .otor-fieid circuit controiihigsim, tsi' "rig-arm, a or out, of high we respectiveiy, terminating upon opposing sets of contacts of said switchorm, anti mechanism, controlled by said iiehhresistance arm in its movement, for si'iiiting said or n from one set of contacts to the other, to vary the motor speed. in a system of speed control for electric motors, the combination with as motor anti its circuit, of an srmatuiestarting, resistance. onii cont ollingerm, a resistance, a controilingi for said resistance mounted neon s shaft and adapted to sweep over the contacts of said resistance, the intcrooiation ii .o motor-fish! circuitof said field resistance by i c' l ingeirm being -conby s n. ting-2127111, a switch-arm, two sources of hire of high and iow voiting noon. opposing segmental. gearing and switch-arm, said esistance controlii i eo contact, being on m from one set ofconthereby varying the mostaitting resistance and its controlling-arm, a:

fielci resistance having a controlling-arm secured to the shaft thereof, said field-res1str once-controlling arm being independent of i the storting-arm and adapted to be set to determine the maximum field resistance to be inserted in the motonfielcl, contacts adapted to he engaged by said startingerm after the armature resistance is out out therebizi shunts about different portions of the fie resistance terminating upon' said contacts, whereby the predetermined maximum field resistancemay be graduaily brought into the field-circuit, a switch-arm, sources of current of high and me voltage, a pair of contacts on each side of said arm, one source of current terminating upon each pair of contacts, and se m cntal gearing connecting the shaft of the fieiid resistance with said switcherrn, adapted at a predetermined point in the operation of said fioid-resisance-controlling arm, to shift said switch-arm from one set of contacts to the other, to vary the motor speed.

'7. In a multiple-voltage system of. speed. control for electric motors, the combination with as motor and its circuit, of an armature resistance, a.controlling-arm therefor, sources of current of'high and low voltage, mechan ism for connecting said armature alternately with said sources of current, a iieid resistance and. acontroller therefor, adapted to he set independently of said controlling-arm, to determine the amount of'field resistance to be inserted. in the field-circuit, and means controlled by said armaturestarting arm, for orin said predetermined resistance into the J ielzd circuit.

In witness whereof I hereunto subscribe STARR You:o 

